Hi Bruce!
I am not a big briner, but will always brine my pork loins.  As Chris mentioned, brining is great for very lean pieces of meat....especially if they need to be cooked longer...like pork loin.
I never brine pork tenderloins as they cook much faster and will hold their moisture if taken off the heat at the right point.
Our Sam's has had tenderloins for $2.08/lb..that's a case price...and they are non-injected and absolutely FABULOUS!!  That's all I have been eating in the pork family lately!  
Because they are rather thin, in diameter, you can really get some great flavors just by rubbing and applying a light glaze.